Besides measuring electricity consumption of home appliances, a smart meter can also monitor load conditions (turning on/off) of the home appliances through a non-invasive manner. In the application of monitoring the load conditions of the home appliances through the non-invasive manner, a computing capability of the general smart meter is inadequate, which can perform identification on real power information, so that the identification accuracy is not high. Another method is to first determine event occurrence through the smart meter, and then power characteristics thereof are uploaded to cloud, so as to perform the load identification at the cloud. In order to accurately obtain a load condition of the electrical appliance, resolution of the smart meter has to be enhanced, though the amount of generated data of the power characteristics is increased. For example, when a sampling rate is 4 KHz, a flow of data uploaded to the cloud by the smart meter is 7.5 KB/s. In view of a system operator, the huge data amount of the power characteristics may increase a bandwidth cost of the cloud, a storage space leasing cost and a calculation cost.